1. Field of the Invention
The invention relates to a liquid crystal display, and in particular to a transflective display.
2. Description of the Related Art
Liquid crystal display (LCD) is widely used in various electronic products such as portable personal computers, digital cameras, or projectors due to slimness and low power consumption.
Unlike conventional cathode ray tube (CRT) and electroluminescent (EL) displays, liquid crystal display panels are unilluminated. Currently, transmissive liquid crystal displays are popular. The backlight source of the display controls light transmission. However, the backlight source accounts for 50% or more of total power consumption, a problem where power conservation is important. Additionally, in brighter environments, the viewability of the transmissive liquid crystal display becomes limited.
Reflective liquid crystal displays suitable for use outdoors and in portable conditions utilize reflection of environmental light rather than a backlight source. Generally, the reflective liquid crystal display comprises twisted nematic (TN) and super twisted nematic (STN) modes.
However, when the environment is dark, viewability of the reflective liquid crystal display is limited.
To improve the display quality in bright environments, increased light intensity of a backlight source is required. Power consumption, however, is increased. Further, the display quality is reduced when directly exposed under sunlight or other light sources, or when the liquid crystal display screen receives sunlight or a light source, surrounding images are reflected.
To improve the problem, the transmissive and reflective liquid crystal displays are combined in a transflective liquid crystal display.
In liquid crystal alignment, the multi-domain vertical alignment (MVA) is used in conventional transflective liquid crystal display. The protrusions disposed on reflective area control the pretilt angles of the liquid crystal molecules. However, such technique is complex, affecting transmissive contrast, aspect ratio, and response speed.